刻板印象激活的无意图性及其大脑神经活动特征

采用启动Stroop范式, 对刻板印象激活的无意图性及其大脑神经活动特征进行了探讨。操纵了启动和“无启动”条件以及与启动所激活的刻板印象一致、冲突和无关的3类靶子词, 记录了36名大学生被试对靶子词进行颜色判别的行为反应和脑电图(EEG, electroencephalogram)。结果发现：(1)“无启动”条件下对3类靶子的反应时基本一致; 启动条件下对一致靶子做出颜色判别的反应时显著快于对冲突靶子的, 对无关靶子的反应时介于两者之间。(2)“无启动”条件下无关靶子诱发的N400波幅最大--显著大于一致和冲突靶子诱发的, 后两者诱发的N400无差异; 启动条件下一致靶子诱发的N400波幅显著小于冲突和无关靶子诱发的N400波幅, 无关靶子诱发的N400波幅也小于冲突靶子诱发的N400波幅。这表明刻板印象激活是一个发生在知觉后加工阶段的具有无意图性的自动化加工过程, 刻板印象激活效应具有抑制冲突信息加工同时促进一致信息加工的“双刃剑”模式, N400可以作为考察这一认知过程特征的电生理学指标。     

Gender Stereotype Activation versus Lexical Semantic Activation: An ERP Study

It is an open question whether social stereotype activation can be distinguished from nonsocial semantic activation. To address this question, gender stereotype activation (GSA) and lexical semantic activation (LSA) were directly compared. EEGs were recorded in 20 participants as they identified the congruence between prime-target word pairs under four different conditions (stereotype congruent, stereotype incongruent, semantic congruent, and semantic incongruent). We found that congruent targets elicited faster and more accurate responses and reduced N400 amplitudes irrespective of priming category types. The N400 congruency effect (i.e., the difference between incongruity and congruity) started earlier and had greater amplitude for GSA than for LSA. Moreover, gender category priming induced a smaller N400 and a larger P600 than lexical category priming. These findings suggest that the brain is not only sensitive to both stereotype and semantic violation in the post-perceptual processing stage but can also differentiate these two information processes. Further, the findings suggest superior processing (i.e., faster and deeper processing) when the words are associated with social category and convey stereotype knowledge.     

性别刻板印象表征的形式及神经基础

本实验采用ERP技术,考察性别刻板印象的表征。结果发现,无论启动是上位范畴、子范畴、典型样例还是反例,被试对于刻板印象不一致的表征比一致的表征均诱发了波幅更大的N400,反应时更长。并且,被试对于性别刻板印象的表征存在层级差异。研究结果表明：（1）性别刻板印象的表征存在层级结构。（2）语义启动下,性别刻板印象违背诱发N400效应。（3）性别刻板印象表征存在自上而下的由大脑额叶进行的语义分类加工。     

The Mechanism Underlying Backward Priming in a Lexical Decision Task: Spreading Activation versus Semantic Matching

Koriat (1981) demonstrated that an association from the target to a preceding prime, in the absence of an association from the prime to the target, facilitates lexical decision and referred to this effect as 'backward priming'. Backward priming is of relevance, because it can provide information about the mechanism underlying semantic priming effects. Following Neely (1991), we distinguish three mechanisms of priming: spreading activation, expectancy, and semantic matching/ integration. The goal was to determine which of these mechanisms causes backward priming, by assessing effects of backward priming on a language-relevant ERP component, the N400, and reaction time (R T). Based on previous work, we propose that the N400 priming effect reflects expectancy and semantic matching/ integration, but in contrast with R T does not reflect spreading activation. Experiment 1 shows a backward priming effect that is qualitatively similar for the N400 and R T in a lexical decision task. This effect was not modulated by an ISI manipulation. Experiment 2 clarifies that the N400 backward priming effect reflects genuine changes in N400 amplitude and cannot be ascribed to other factors. We will argue that these backward priming effects cannot be due to expectancy but are best accounted for in terms of semantic matching/ integration.     

Automatic semantic activation is no myth: semantic context effects on the N400 in the letter-search task in the absence of response time effects

The claim that semantic activation is an automatic process was recently called a myth, on the basis of the finding that if letter search is performed on a prime word, semantic priming effects on response time are eliminated, whereas repetition effects are preserved. The absence of semantic activation, however, cannot be validly inferred from the lack of response time effects, and converging evidence is needed. To this end, we examined the event-related potential correlate of priming, the N400 amplitude modulation, in a letter-search priming paradigm. Our experiment replicated the response time effects and demonstrated that the N400 amplitude successfully differentiates cross-case repetition priming, semantic priming, and neutral conditions. The results clearly indicate that the meaning of the prime word was processed and that semantic activation indeed was present in the letter-search task. The notion that semantic activation is an automatic process should not be abandoned prematurely.     

基于面孔知觉的刻板印象激活两阶段模型

从个体建构研究视角出发, 考察了基于面孔知觉的刻板印象激活过程。实验一比较了性别分类判断、启动范式以及同时呈现范式下刻板印象匹配性判断三者所用反应时的差异, 结果发现, 后者显著地大于前二者, 且等于前二者之和; 面孔倒置呈现使同时呈现范式下刻板印象匹配判断的反应时和错误率显著增大, 但其对启动范式中刻板印象匹配判断的反应时和错误率没有影响。实验二基于同时呈现范式, 通过不同程度的面孔变形来操纵性别类别提取的难度, 更精确地探讨了基于面孔知觉的社会类别信息提取过程对刻板印象激活的影响, 结果表明, 随着从面孔中提取类别信息难度的增加, 刻板印象激活所用的反应时也逐渐增大。研究结果证实了研究者所提出的刻板印象激活两阶段模型, 即基于面孔知觉的社会类别提取阶段和刻板印象信息激活阶段, 证实社会类别激活和刻板印象信息激活是两个分离的过程, 以社会类别信息提取为目的的面孔知觉对刻板印象的激活有显著影响。     

高度模糊靶字下的N400语义启动效应：词汇加工理论的证据

本研究基于不可识别模糊字词仍能诱发N400的词汇加工理论的假设,让被试对模糊字进行同一字延迟判断,利用脑电技术记录不同模糊程度靶字的认知过程,来探讨N400出现的条件,以阐明N400反映的是词汇加工,还是词汇后加工。实验结果表明：与可识别、轻度模糊汉字一样,不可识别、高度模糊汉字仍然可以诱发N400;这种N400语义启动效应反映了词汇加工过程。     

任务与字频对汉字情绪启动反转效应的影响

本研究使用ERP技术对比了效价判断与真假字判断两种任务形式下的汉字情绪启动效应。结果发现,在效价判断任务中高频目标字出现情绪启动的反转效应,效价不一致比一致条件下反应时短,诱发了较大的P200;低频目标字出现情绪启动的一致性效应,效价一致比不一致条件下反应时短,诱发了较大的P200与N400。真假字判断任务中高频和低频目标字均出现情绪启动的一致性效应。情绪启动的反转效应依赖于刺激材料的可通达性与注意导向,启动字与目标字的反应竞争关系导致了情绪启动的反转效应。     

听障儿童认知抑制控制的脑电特点

通过认知抑制控制的Stroop范式运用事件相关电位考察听障儿童和对照组儿童在认知抑制控制方面的行为特点以及脑内时程特点。行为结果显示：（1）两类被试在一致条件下认知抑制控制的正确率显著高于不一致条件,反应时显著快于不一致条件,表现出冲突效应;（2）组间结果显示,听障儿童的认知抑制控制正确率显著低于对照组儿童,反应时上差异不显著。脑电结果显示：（1）不一致条件在N450上的负激活显著高于一致条件,听障儿童比对照组儿童诱发了更负的N450波幅;（2）不一致条件在SP上的正激活显著高于一致条件,两类被试在SP上差异不显著。结果提示听障儿童在认知抑制控制过程中的冲突监测功能存在障碍,这是由于冲突监测过程中注意分配能力受损所致。     

汉字识别中字形畸变和语境的ERP效应

以事件相关电位（ERP）技术和语义启动范式,采用同一字判断（靶字延迟反应）作业,考察字形畸变和语境对低频汉字识别的影响。结果发现,无语义启动时,畸变靶字正确率低于清晰靶字;启动效应只体现在畸变时的正确率上。150–300ms窗口,畸变字比清晰字诱发峰值更负的N170;300–500ms时间窗口,不启动条件诱发平均波幅更负的N400,畸变字诱发更大N400。结论是,畸变字诱发的N170成分,在一定程度上反映了字形加工;N400的语义启动效应和畸变效应,扩展Holcomb的研究,并支持语义提取理论。     

双语即时切换下非目标语言语音和语义的激活状态

本研究采用双语即时切换范式, 探讨非熟练中英双语者在对目标语言(启动词)语音或语义的加工过程中非目标语言的激活状态。实验1设置了与启动词的翻译对等词存在语音相关或无关的两类配对词, 要求被试进行语音判断任务, 结果表明, 不论哪种切换条件, 两类配对词在反应时和P200成分上都没有差异, 说明目标语言在语音加工过程中非目标语言的语音层面没有得到自动激活, 从而没有产生启动效应。实验2则设置了语义相关和无关配对词, 并进行语义判断任务, 结果在两种切换条件下都发现明显的语义启动效应及N400差异, 说明非目标语言在语义层面上有得到自动激活, 但激活的程度表现出切换方向上的不一致, L1-L2切换下的语义启动量要明显大于L2-L1, 并且L1-L2的N400差异主要表现在前部脑区, 持续时间更久, 而L2-L1的N400差异主要表现在后部脑区, 但持续时间较短, 表明对于非熟练的双语者来说, 不同切换方向下对共享语义表征的激活加工是不一样的。     

Different brain mechanisms between stereotype activation and application: evidence from an ERP study

Stereotyping involves two processes in which first, social stereotypes are activated (stereotype activation), and then, stereotypes are applied to given targets (stereotype application). Previous behavioral studies have suggested that these two processes are independent of each other and may have different mechanisms. As few psychophysiological studies have given an integrated account of these stages in stereotyping so far, this study utilized a trait categorization task in which event-related potentials (ERPs) were used to explore the brain mechanisms associated with the processes of stereotype activation and its application. The behavioral (reaction time) and electrophysiological data showed that stereotype activation and application were elicited respectively in an affective valence identification subtask and in a semantic content judgment subtask. The electrophysiological results indicated that the categorization processes involved in stereotype activation to quickly identify stereotypic and nonstereotypic information were quite different from those involved in the application. During the process of stereotype activation, a P2 and N2 effect was observed, indicating that stereotype activation might be facilitated by an early attentional bias. Also, a late positive potential (LPP) was elicited, suggesting that social expectancy violation might be involved. During the process of the stereotype application, electrophysiological data showed a P2 and P3 effect, indicating that stereotype application might be related to the rapid social knowledge identification in semantic representation and thus may be associated with an updating of existing stereotypic contents or a motivation to resolve the inconsistent information. This research strongly suggested that different mechanisms are involved in the stereotype activation and application processes.     

Self‐Construal Scales Lack Validity

Self‐construal is thought to mediate and explain the effects of culture on a wide variety of outcome variables. A meta‐analysis of published cross‐cultural self‐construal research is reported in this article, and the results across studies suggests that the evidence for the predicted cultural differences is weak, inconsistent, or nonexistent. The results of 3 priming experiments (N = 121, N = 99, and N = 361) suggest that (a) priming does not account for the inconsistent results observed in the meta‐analysis, (b) that scores on a self‐construal scale appear to be measuring trait‐like constructs that are not sensitive to priming, and (c) that measures of self‐construals lack convergent validity. The results of several measurement studies (N = 121, 223, 230, 323, 214, 206, 126, 204, 148, 141, and 150) were inconsistent with the a priori two‐factor measurement model in every case. Self‐construal scales were found to be radically multidimensional and highly unstable within and across cultures. These results lead us to conclude that catastrophic validity problems exist in research involving the use of self‐construal scales in cross‐cultural research.     

义符启动范式下家族大小和类别一致性对义符语义激活的影响

采用义符启动范式,考察不同加工深度任务中家族大小和类别一致性对义符语义激活的影响。结果发现:在词汇判断中,家族大小影响义符的语义激活,大家族义符的语义不容易激活,小家族义符的语义容易激活。在语义相关判断中,类别一致性影响义符的语义激活,类别一致性高的义符的语义容易激活,并且在错误率上,这一影响受义符的家族大小调节。义符类别一致性影响义符家族效应的作用方向:当类别一致性低时,出现抑制的家族效应;当类别一致性高时,家族效应无影响或表现为促进作用。     

Priming effects on the N400 in the affective priming paradigm with facial expressions of emotion

We studied the effect of facial expression primes on the evaluation of target words through a variant of the affective priming paradigm. In order to make the affective valence of the faces irrelevant to the task, the participants were assigned a double prime–target task in which they were unpredictably asked either to identify the gender of the face or to evaluate whether the word was pleasant or unpleasant. Behavioral and electrophysiological (event-related potential, or ERP) indices of affective priming were analyzed. Temporal and spatial versions of principal components analyses were used to detect and quantify those ERP components associated with affective priming. Although no significant behavioral priming was observed, electrophysiological indices showed a reverse priming effect, in the sense that the amplitude of the N400 was higher in response to congruent than to incongruent negative words. Moreover, a late positive potential (LPP), peaking around 700 ms, was sensitive to affective valence but not to prime–target congruency. This pattern of results is consistent with previous accounts of ERP effects in the affective priming paradigm that have linked the LPP with evaluative priming and the N400 with semantic priming. Our proposed explanation of the N400 priming effects obtained in the present study is based on two assumptions: a double check of affective stimuli in terms of valence and specific emotion content, and the differential specificities of facial expressions of positive and negative emotions.     

Schema‐driven source misattribution errors: remembering the expected from a witnessed event

When recollection is difficult, people may use schematic processing to enhance memory. Two experiments showed that a delay between witnessing and recalling a visual sequence increases schematic processing, resulting in stereotypic memory errors. Participants watched a slide show of a man and a woman performing stereotype‐consistent and stereotype‐inconsistent actions, followed by an immediate or delayed memory test. Over a two‐day delay, stereotype‐inconsistent actions were increasingly misremembered as having been performed by the stereotype‐consistent actor (Experiment 1). All the source errors increased, regardless of stereotype consistency, when the wrong actor was suggested. When we merely suggested that ‘someone’ performed an action (Experiment 2), only stereotype‐consistent source errors were increased. Although visual scenes are typically well remembered, these results suggest that when memory fades, reliance on schemata increases, leading to increased stereotypic memory errors. Copyright © 2007 John Wiley & Sons, Ltd.     

负启动效应的认知神经科学研究

近几年,对负启动效应的神经机制研究发现,干扰项抑制与情节提取都是引起负启动的原因,究竟哪种机制起主要作用与实验任务有很大的关系。从现有的研究结果来看,位置负启动与前额皮层有关,EPR上表现为P1和N1波幅减小或N2波幅的增大,支持抑制机制。特性负启动P3成分仍存在不一致的结果,脑区的广泛激活模式使得研究者越来越倾向采取整合的观点。     

词汇加工初期语义属性的激活程度:来自ERP的证据

运用事件相关脑电位（ERP）技术,采用快速掩蔽启动范式和Go/Nogo范式,探讨汉语重复启动和语义相关启动中语义激活程度的差异和特点。实验中要求被试执行一个额外的语义判断任务,对关键刺激不做明显的行为反应。结果发现,在重复启动条件下获得了稳定的N400效应,语义相关启动条件下没有N400效应;重复启动和语义相关启动条件均未产生N250效应。在较短的SOA条件下,词频对语义的激活和加工不产生影响。     

汉-维非熟练双语者非目标语言语音激活与语义激活差异的ERP研究

采用跨语言中介启动范式,通过两个2(词对类型)*2(启动方向)被试内的ERP实验,探讨非熟练汉-维双语者非目标语言语音激活与语义激活状态的差异。结果表明:(1)L2-L1启动方向下,语音相关词对与无关词对诱发P200峰值差异更大,潜伏期更长。(2)L1-L2启动方向下,语义相关词对与无关词对诱发N400峰值差异更大,潜伏期更长。结论:(1)在加工目标语言时非熟练汉-维双语者非目标语言词汇层与概念层都激活。(2)当非目标语言是汉语时语音激活强度大,激活速度较慢;语义激活强度较小,激活速度较快。(3)当非目标语言是维吾尔语时语音激活强度小,激活速度较快;语义激活强度较大,激活速度较慢。     

Don’t stereotype, think different! Overcoming automatic stereotype activation by mindset priming

Automatic stereotype activation can be overcome intentionally and after an extensive training. However, intentions have to be tailored to a certain social category. It is hypothesized that activating the mindset “think different” by priming creativity prevents stereotypes and associations in general from becoming automatically activated. In two experiments a creative, a thoughtful or no mindset was activated. Afterwards, the activation of associations was measured using a lexical decision task with semantic priming. As predicted, the automatic activation of stereotypes (Study 1) and other associations (Study 2) was found in the control conditions but not in a creative mindset. These results suggest that people possess a mindset that allows for overcoming automatic stereotype activation without being tailored to a specific category.